1. Field of the Invention
The present invention relates to a steering control device for controlling a steering action of a vehicle making use of magnetic forces on the basis of a magnetic signal given by each magnetic nail buried in a road at intervals.
2. Description of the Related Background Art
Steering control devices are known (for example, in Laid-open Japanese Patent Publication No. 8-314541) which make use of a magnetic force generated from each magnetic nail buried in a road at intervals to control steering of a vehicle to enable automatic traveling. Such steering control devices normally detect a magnetic signal given by each magnetic nail, making use of a magnetic sensor provided on a vehicle, calculate an amount of steering control such that the magnetic signal is increased in level, and drive a steering actuator in accordance with the calculated amount of steering control.
Such conventional steering control devices, however, have problems in finding difficulty in precisely calculating an amount of steering control in accordance with a magnetic signal given by each magnetic nail in the case where a magnetic sensor itself does not work well due to malfunction or the like, magnetic nails are buried at non-uniform intervals, or a vehicle enters a road in which any magnetic nail is not buried, since the magnetic sensor detects a level of a magnetic signal given by each magnetic nail and an amount of steering control is calculated relying on only an output signal of the magnetic sensor.